Using the QCD Operator Product Expansion, we derive the real part of the transverse and longitudinal vector vector correlation function with the ρ, ω quantum numbers to leading order in density and in q2 at -ω2 → ∞. To dimension 6, only twist-2 and 4 operators contribute. These OPE, through the energy dispersion relation, provide model independent constraints for the q dependence of the vector meson spectral density in nuclear medium. We further make a QCD sum rule type of analysis to extract the momentum dependence of the vector meson dispersion relation in medium. The contributions from twist-2 operators are added up to infinite order to check the validity of the OPE at the relevant Borel window.
Bibliographical noteFunding Information:
This work was supported in part by the KOSEF through grant no. 971-0204-017-2 by the Korean Minsitry of Education through grant no. BSRI-98-2425.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics